左旋聚乳酸的改性实验  

Modification experiment of poly-L-lactic acid for biodegradable stent

作　　者：陈宝爱[1] 谷雪莲[1] 

机构地区：[1]上海理工大学医疗器械与食品学院,上海市200093

出　　处：《中国组织工程研究与临床康复》2011年第51期9629-9632,共4页Journal of Clinical Rehabilitative Tissue Engineering Research

摘　　要：背景:目前临床上大量使用的金属支架永久存留于人体,对人体存在潜在的风险。目的:观察改性对左旋聚乳酸的作用以及改性材料用于可降解支架制备的可行性。方法:以左旋聚乳酸/聚己内酯为95:5的比例,用溶液法制备左旋聚乳酸、聚乳酸/聚己内酯共聚材料(PLCL-J9505)和聚乳酸/聚己内酯共混材料(PLCL-H9505)薄膜。结果与结论:力学性能测试结果显示,3个月左旋聚乳酸材料的脆性明显升高,材料变得容易断裂,成为制备支架的一大缺陷;PLCL-J材料力学性能损失过快,第3周屈服完全消失,第4周拉伸强度开始急剧下降,到第10周已经完全丧失力学性能;PLCL-H材料不仅初始时断裂伸长率高,而且在降解过程中能始终保持较高的弹性。特性黏数测试和表面形态观测结果显示PLCL-J材料的降解速率过快,不适合在支架上应用,而左旋聚乳酸和PLCL-H基本是匀速的水解,且PLCL-H相对于左旋聚乳酸降解速率有一定程度的增加。提示左旋聚乳酸与聚己内酯共混改性比例为95:5时不仅能保证材料具备支架所需的力学强度,还能显著提高材料的断裂伸长,达到了增塑目的的同时,也加快降解速率,有望成为制备可降解支架的新型材料。BACKGROUND：Current,metal stents mostly used in clinic will permanently stay in the human body,and they can provide potentially risks to human body.OBJECTIVE：To observe the effects of modification on poly-L-lactic acid（PLLA） and the feasibility of preparation of biodegradable stents with modified materials. METHODS：PLLA,polylactic acid/polycaprolactone（PLCL-J） and PLLA/polycaprolactone（PLCL-H） films were prepared by solution method with the modification ratio of PLLA/polycaprolactone of 95/05.Comparative observation of changes in mechanical property,intrinsic viscosity and mass loss,and changes in surface morphology of PLLA,PLCL-H and PLCL-J was performed with film degradation test. RESULTS AND CONCLUSION：Mechanical property test showed that the brittleness of PLLA materials was significantly increased after 3 months.The materials were easy to break,and this was a major defect in preparing stents;the mechanical properties of PLCL-J lost too fast,its yield completely disappeared at 3 weeks,its tensile strength began to decline sharply at 4 weeks,and its mechanical property completely disappeared at 10 weeks;PLCL-J material not only had high initial breaking elongation,but also kept a high flexibility during the degradation process.Intrinsic viscosity detection and surface morphology observation showed that PLCL-J material was not suitable for stent preparation based on its fast degradation rate,while the degradation rates of PLLA and PLCL-H materials were uniform,and the degradation rate of PLCL-H material was increased compared with PLLA material.The blending material of PLLA and polycaprolactone with modification ratio of 95/05 can not only ensure the mechanical strength of stents,but also increase breaking elongation of stents,and these make it can be used as a new type of material for preparation of biodegradable stents through an increase in plasticization and degradation rate of the material.

关 键 词：共混改性 聚乳酸 聚己内酯 共聚 可降解支架 

分 类 号：R318[医药卫生—生物医学工程]